dry run with dryer

[Boman]

I think we have discussed this before, but how much percentage over rated capacity is normal for an empty dryer to heat?

I know they will get hotter than called for on the working/cycling stat, but I tried one today that shows a stat rated at 155-25. If the 25 means it can go that much either way, I am okay. This thing got to almost 180 degrees before kicking off. I would expect somewhere around 155 and 130 with a little either way when empty.

Whlpl model - tedx64jq1
Working/cycling stat pn shows to be 3387134 (http://www.repairclinic.com/referral.asp?R=153&N=2893)

[jeff1]

This differential may be displayed on the part and could be 10-40? or more. If displayed on the part, it would look something like L150-20, the 20 being the differential between cut out and cut in.

140-160 would be a 20? differential.
Heating up to 180? is too hot!

548 Dryer cycling thermostat with internal bias heater, L155-25 Manufacturer Number 3387134 (http://www.repairclinic.com/referral.asp?R=153&N=2893)

jeff.

[thefixer]

That's not how it works. The L155-25F means the thermostat opens at 155? and closes at 130?.

[jeff1]

The L155-25F means the thermostat opens at 155? and closes at 130?

That's what I said.

jeff.

[thefixer]

I thought your answer was confusing. For a thermostat marked L155-25 he asked, "If the 25 means it can go that much either way". You didn't answer that and gave an example of an L150-20 stating that the 20 was the differential and then stated 140-160 would be a 20? differential implying that the L150 would go between 140-160 for the 20? differential.

Just wanted to make it clear that the 155 is the cut out temp and the -25 would give the cut in temp of 130.

[Boman]

The L155-25F means the thermostat opens at 155? and closes at 130?

That's the way I thought I remembered from years ago. But, I think I have been told lately that they will get a little hotter when empty. I never understood this statement. 155 degrees is 155 degrees in my mind. I can understand a little fluctuation but as much not as some I have seen.

Anyway, I will change the stat on this one and see if I can get that temp down.

Can the cycling stat ohm within specs and still be bad? If that is the problem?

[thefixer]

You need to do a controlled test on the thermostat on a hot plate to determine if it is operating within specs. It should operate within 5% of rated temperature. A static test with ohmmeter at room temperature only tells you if the switch is closed as it should be. How and where are you testing the dryer temperature?

[jeff1]

Can the cycling stat ohm within specs and still be bad? If that is the problem?

Of course it can be bad....that is a part that is electrical and mechanical....electrical can ohm ok all day but the mechanical part of the thermostat can fail and be bad.


I thought your answer was confusing.

I can see that. The 140-160?F was simply an example of what a 20? differencial was.


That's not how it works


This differential may be displayed on the part and could be 10-40? or more. If displayed on the part, it would look something like L150-20, the 20 being the differential between cut out and cut in.

This IS how it works.
With a difference of opinion it is best not to make a blanket statement "That's not how it works"

jeff.

[Boman]

I tested inside my shop. Ambient temp around 60 degrees. I test with a pocket thermometer in the exhaust. I haven't seen my ho tplate in years. Does an oven fluctuate too much to use for this purpose?

[jeff1]

I haven't seen my ho tplate in years.

Some electric frying pans had a temp control you can use to help test at certain temps.


Does an oven fluctuate too much to use for this purpose?

Probably. Plastic body part wouldn't take the heat either.

jeff.

[Boman]

This is confusing.

Jeff, are you saying a thermostat marked L155-25 will cut on and off at 12.5 below and 12.5 above 155 to make a 25 degree differential?

[jeff1]

It will cut off/open at approx 155?F and wait until is has cooled down the approx 25?F cooler and reclose.

jeff.

[Boman]

Now that I understand and is the way I remembered.

Thanks to both you fellas for getting me back on the right track.

*****

Bottom line is your 180?F is way too hot.

jeff.

[Boman]

Tried 3 different cycling stats on this dryer. One was a new one. All rated L155-25. Non of them dropped back to 130 before kicking back in. Nor, did they kick off at 155. They acted more like 1/2 the differential above and half below the 155. Like I first understood you to say, Jeff.

Not sure how accurate my 3 clip-on thermometers are nor my infra-red leak detector.

[jeff1]

Checked your thermometer to make sure it is accurate?

jeff.

[Boman]

Only way I know to check them is put them outside and see which, if any, match.
I thought these calibrated by turning the nut on them. Trouble is, I am not sure how to calibrate these. The nut seems tight. Hold the dial and turn the nut? You ever calibrated one of these clip-on pocket thermometers?

[jeff1]

The nut seems tight. Hold the dial and turn the nut?

Correct.

jeff.

[Boman]

Got a stove going yesterday that gives the temp (digital) you set it on as you turn the knob. Mayb I could take the thermometers out of the sleeve/sheath and check them in the oven?

Or would the temp in the oven vary too much? I mean the temp read out will just be an average temp, right? Guess I could watch the thermometer and average the temp swings to see if the average is close to what the read out says.

[jeff1]

Got a stove going yesterday that gives the temp (digital) you set it on as you turn the knob. Mayb I could take the thermometers out of the sleeve/sheath and check them in the oven?

Whats the max temp of your thermometer?
Many of the lens covers look like glass but are plastic.


Or would the temp in the oven vary too much?

For sure it would....heats above the set temps and shuts off, cools below the set temp and comes back on.

jeff.

[Boman]

Good point about the thermometer lenses. Been there done that with an industrial thermometer that I had laying around in the shop. It was actually meant to be screwed into a boiler or something that gets VERY hot. Thought something kind of smelled funny when I noticed the lense was starting to melt from the oven heat.

The A-Z here burned a few weeks ago, not sure when they will be back up and running. I guess I need to find me a new pocket clip-on thermometer to check these with. But who knows how accurate they are when new?

Thanks

[jeff1]

Some of those pocket style ones are getting hard to find...

Pocket thermometer, -40? to 160? F (http://www.shareasale.com/r.cfm?u=196151&b=71869&m=11664&afftrack=&urllink=www%2Ea%2D1appliance%2Ecom%2Fproduct%2FT16 0%2DUEIT160)

jeff.

[Boman]

Let me tell you what I did.I replaced the element in a Kenmore model - 110.86873100 with one from a whlpl model - TEDX640JQ1 that I had here. The cage fit. I sold it. Guy complains it is not running. This is after I have run it several times in my shop. He had lost one leg of power. We flipped the breaker, power was regained. Later that day or the next he called and said it was not getting hot. Same thing, lost power on one leg, evidently the opposite leg. He told me his old dryer had been running and just quit like this one had done earlier.

At this point I decided to take the dryer back and told him he might want to get someone to check his breaker panel. For what it worth, I saw a **** roach crawling across the breakers in the box.

Since the dryer did seem to be getting too hot, I decided to order the element that is called for for the dryer. Put it in, and it seems to cycle funny. For one thing, it does seem to want to get hot enough to cycle until I put the temp control on low. At that point it will get to about 150 then cycle back, act about right. The stat is L150-20.

This stat is the stat with a seperate stat heater. I am thinking of switching replacing it with a stat with the built-in heater that is rated L155-25. There is only a couple of degrees difference in the average temp between the two stats.


I am confused as to why these stats, the 3 I referred to earlier, one being a new one, let the dryer show to be so hot. I have synced two of my thermometers.

Why would one element get so hot? Different wattage rated? If so, why would the stanot still regulate the heat andnot let it get so hot?

Sounds to me like I may have an air flow problem somewhere. I may have to change the drum as I did a little damage to the rear felt while truning the drum by hand trying to get it on the rollers and straighten the belt. I did realize the exhaust tube was catching part of the felt as the drum turned and the tube was still loose.

I thought it was still sealing off, but it might not have been. Still looks like the stat should have been cycling the heat.

One more thing that needs top be mentioned is I have a test cord for dryers made of 10 gauge wire that I plug into an old welder line with a stove recep on it. I did a little carving on the rec on the extention/test cord to let a dryer and/or stove plug fit. I noticed on the primary stove rec, one side had shown signs of getting hot or arcing. Thi smade me think maybe the dryer was kicking breakers off at the customers old house. It might not at my shop because the power is coming from like 60 amp fuses. This is only used for testing 220 appliances.

Enough for now. Comments appreciated.

[jeff1]

110.86873100

550 551 Heating element, 240 volts, 5200 watts.


TEDX640JQ1

552 This Whirlpool dryer heating element is rated 240 volts and 5400 watt

These are two different style elements.


Guy complains it is not running. This is after I have run it several times in my shop. He had lost one leg of power. We flipped the breaker, power was regained. Later that day or the next he called and said it was not getting hot.

He has a power issue for sure.


I decided to order the element that is called for for the dryer. Put it in, and it seems to cycle funny. For one thing, it does seem to want to get hot enough to cycle until I put the temp control on low

High was lower than low??


This stat is the stat with a seperate stat heater. I am thinking of switching replacing it with a stat with the built-in heater that is rated L155-25. There is only a couple of degrees difference in the average temp between the two stats.

Try not to change the temps more than 5? if you are going to sub out thermostats.

jeff.

[Boman]

When set on high temp, it does seem to be just a little cooler. Like it eventually gets right at the temp to cut off and basically just stays there. Set it on the lower temp and it will heat up the other couple of degrees and cycle back off.

Strange.

[jeff1]

How cold is the air coming into the dryer?

jeff.

[Boman]

This did cross my mind. Didn't know whether ambient temp would have any affect on the dryer stats if the heat coming across them is the temp that should make it cycle.

Guessing yesterday somewhere around 60, shirt sleeve temps.

I will heat the shop a little today and see if there is a difference.

P.S. I can see where the ambient temp can make the dryer take a little longer about heating up.

[jeff1]

Normal room temp is 68-71?F....gotta wonder if we suck in 50-60?F air, how much would that effect things.

jeff.

[Boman]

May be. I thought I had found the problem. I noticed some paperwork that came with the new element. It was some directions. said if replacing these elements use hole "A", if replacing these elements, use hole "B". I had use hole "A". Changed to "B". No real difference. It did cycle a time or two. Mostly it gets to or near the high temp and just runs there unless I turn the temp control.

Sure seems to feel hot, but 150 would be hot feeling if you keep your hand close to it any length of time.

It did cycle a time or two with the single unit stat in it, but I think I will just use what it calls for (for liability reasons), even though there is very little difference in the temps.

Thanks, I think I may order me a couple new thermometers. Mine have been dropped several times and I have nothing to calibrate them with.

[jeff1]

Mine have been dropped several times

Ooops!


and I have nothing to calibrate them with.

Instructions


Ice Water Method
1.

Fill a glass with as much crushed ice as you can and fill the remainder of the space with distilled or filtered water. If you do not have distilled or filtered water, use clean tap water.
2.
Stir the ice chips and water.


3.
Insert the thermometer's probe or stem into the middle of the glass so that it is not touching the bottom or sides of the glass. Submerge at least 2 inches of the probe into the ice bath.
4.
Hold the stem in the ice bath for 30 to 60 seconds.
5.
Adjust the hex adjusting nut under the head or dial of the thermometer so that the temperature reads 32 degrees F, which is the freezing point of water. If you have a digital thermometer, press the reset button to adjust the temperature.

Boiling Water Method

6.
Pour tap water into a cooking pot and place it on the heat of a stove top element; bring the water to a rolling boil.
7.
Place the stem or probe into the boiling water so that at least 2 inches of the stem is immersed; the stem should not be touching the sides or the bottom of the pot.
8.
Hold the stem in the water for 30 to 60 seconds.
9.
Adjust the hex adjusting nut under the head or dial of the thermometer so that the temperature reads 212 degrees F, which is the boiling point of water. If you have a digital thermometer, press the reset button to adjust the temperature.

jeff.